Hi guys, progress update:

I have increased the size of the ball socket to just slightly over 5mm. That will allow for some play and if it's too loose it's easier to just put a coating on the ball joint.

I went to save the file to STL format for printing, but first applied an STL check modifier. It came up with a few errors, but I couldn't locate them. So I managed to find a program called Netfabb which highlights the errors in the model.

It turned out that 3DS had added a few vertices around the model right on top of other verts. So when you select what looks like one vert, you find 2 or more. Weird. So I just need to go around the model and weld them all together.

Earlier this week I checked out some 3d printing websites and found a couple that looked decent (in terms of variety of materials and reasonable pricing etc). I sent off quotes using their webforms, but haven't heard anything yet. Not sure if they cater to individuals or prefer more commercial orders. If I don't hear anything I'll check out shapeways (once the errors in the model have been corrected).

So shouldn't be too long now, I'll keep you informed. Hopefully will get more time this weekend to move it along.